A ruthenium-containing material for thin film formation exhibits specific electric characteristics and has found wide applications. For example, a ruthenium thin film has been used as an electrode of memory devices typified by DRAM devices, a resistant film, a diamagnetic film used in the recording layer of hard disks, and a catalyst for polymer electrolyte fuel cells.
Processes for forming the above-described thin film include sputtering, ion plating, MOD techniques such as a dipping-pyrolysis process and a sol-gel process, and chemical vapor growth techniques. Chemical vapor growth techniques (hereinafter abbreviated as CVD) including atomic layer deposition (ALD) is the most suitable for many advantages, such as compositional controllability, excellent step coverage, suitability to large volume production, and capability of hybrid integration.
Various ruthenium compounds are known as raw materials for CVD. For example, Patent Literature 1 below discloses a ruthenium compound having two carbonyl groups and two ketoimine groups having a specific structure but does not mention about the ruthenium compound of the present invention. The ruthenium compound of Patent Literature 1 is not sufficiently satisfactory as a material for CVD because of its melting point of 100° C. or higher.